Liquid fuel burner



p 9 L. s. CHADWICIK ET AL 2,205

LIQUID FUEL BURNER Filed Aug. 15, 1934 5 Sheets-Sheet l INVENTORS, in i .QQQLM w BY mummmw m M ,M AM

' ATTORNEYJ L. s. CHIADWICK ET AL Sept. 7, 1937.

LIQUID FUEL BURNER Filed Aug. 15, 1934 5 Sheets-Sheet 2 Sept. 7, 1937.

L. S. CHADWICK ET AL Lag LIQUID FUEL BURNER Filed Aug. 15, 1954 Moon ,uaoon 3/ Moose 27 .uaao aa 0000L- uOUO 00 i5 0O00uL- 000 00 j 22 0 24 Q29 0 L /6 I 38 Z 9 9 ji sl I 5 Sheets-Sheet 5 INVENTORJ ATTORNEYS Sept. 7, 1937. 1.. s. CHADWICK, ET AL 2,092,205

LIQU ID FUEL BURNER BY \AMAMW GW,MMM

ATTORNEYS v pt. 7, 1937. L. s. cHADWlcK ET AL 2,092,295

LIQUID FUEL BURNER Filed Aug. 15, 1954 5 Sheets-Sheet 5 ATTORNEY-5 Patented Sept. 7, 1937 rear ()FFlCE LIQUID FUEL BURNER poration of Ohio Application August 15, 1934, Serial No. 739,908

'7 Claims.

In the use of oil burners of certain types, difficulties arise from the presence of water in the fuel. For example: If the structure is such that heat will be transmitted from the space wherein combustion occurs to a point below the body of oil from which the burner receives its immediate supply, and said heat is sufiicient to convert any water that has settled at said point into steam,

the steam pressure Will force excess oil into the combustion space and cause flashing or an un-' controllable high fire and, in general, create a very hazardous condition.

It is the broad purpose of our invention to obviate this diiiiculty by providing an oil burner involving a fuel container having a steam space adjacent its top, and a water collecting space at its bottom that is in suiiiciently intimate heat exchanging relation to the combustion space as to result in its temperature being raised above the boiling point of water when the burner is in operation, and venting the steam space, preferably into the combustion space so that any oil escaping with the steam will be consumed, thus avoiding obnoxious odors.

A further object is to separate the oil from the steam before it escapes, and to this end we employ bafiies in advance of the vent of the steam.

space for arresting all or as high a percentage as possible of oil with which the steam is laden.

The invention had its conception in connection with the combustion device or burner set of an oil fired intermittent absorption refrigerating machine; but, as will be evident from the present disclosure, it is not limited to this particular kind of burner.

The'difficulties above referred to, encountered in the combustion devices or burner sets of refrigerating machines of the class just mentioned gave rise to an invention that constitutes the sub- 40 ject matter of a copending application filed by Karl W. Rausch, on August 12, 1933, Serial No. 684,869, now Patent No. 2,032,853, and which invention, broadly, resides in means for preventing the simultaneous feeding of two constituents of a liquid body that differ in specific gravity such, for example, as kerosene and water. According to the Rausch invention, flow of the fuel is prevented in the presence of a perceptible amount of water. 4

The particular type of burner in connection with which this and the Rausch inventions originated includes a burner bowl in the nature of a relatively deep annular channel that is connected at diametrically opposite points to a supply pipe Oil is delivered to the burner bowl through the supply pipe and feed tubes from a dispensing receptacle over which a bottle-like reservoir is supported in inverted position so that the same operates on the well known barometric or pigeon fount principle to maintain 5' a constant oil level in said receptacle and in the burner bowl. A so-callecl lighting ring, which is in the nature of a cylindrical wick of asbestos or the like, reposes within the burner bowl and projects a slight distance above the same to provide 10 a vaporizing area to which oil is fed by capillary attraction from the supply in the burner bowl. Supported above and in operative relation to the bowl are the usual perforated commingling tubes enclosed by a drum or chimney. 15

The operation of this particular type of burner is so adversely affected by water in the oil as to produce the highly dangerous conditions hereinbefore referred to; and in this connection it may be pointed out that it is not at all unusual to find 20 water in perceptible quantity in oil supplied for burners of this character.

The accepted analysis of what causes the trouble in the type of burner just described is as follows: The burner bowl becomes quite hot due to 25 its proximity to the combustion space the lower portion of which is immediately above the lighting ring or wick, and because of its contact with the highly heated commingling tubes, the heat is conducted through the feeding tubes to the 30 main supply pipe so that the tubes and a part of the pipe reach a temperature above the boiling point of water. When even a small amount of water comes in contact with these highly heated parts the water flashes into steam that escapes 35 through the feed tubes and blows the oil vapor, and in many cases drops of the hot oil, up into the burner drum or chimney. At times the action is so violent as to blow the lighting ring out of the burner bowl. The oil thus thrown into the 40 hot burner causes a high blaze, which may overheat the burner set, even to the inclusion of the fuel reservoir, and start a serious fire.

The present invention differs from that of Rausch in that it permits feeding of both the 45 oil and water to the burner and there harmlessly disposes of the latter by providing a water collecting space or sump that is maintained during burner operation at a temperature above the boiling point of water, where water present in the 50 oil will collect and be evaporated; and a steam space of relatively large volume above the oil surface, which is suitably vented, preferably adjacent to the wicks (or so-called lighting rings in the particular type of burner herein disclosed),

to the end that the steam may escape gently, or in such manner as not to force slugs of oil ahead of it, into the zone of combustion so that any oil carried with it will be consumed, as previously stated. In its preferred embodiment, the invention includes'oil arresters or baffles in advance of the vent of the steam space which serve to separate from the steam oil which may be mixed with it.

More limited objects of the invention are to provide an eflicient and relatively simple burner structure, composed in most part of die-formed sheet metal elements that may be readily fabricated into a compact and sturdy structure possessing the features hereinbefore pointed out and operating in a safe and highly satisfactory manner.

The invention, embodied in a combustion device or burner set for an oil fired intermittent absorption refrigerating machine, is illustrated in the accompanying drawings, and while we shall proceed to describe the same in detail it will be understood that the invention, in its broader aspect, is not limited to the structural details shown further than is required by the terms of the appended claims.

In the drawings, Fig. 1 is a side elevation, and Fig. 2 a plan View, of a combustion device or burner set incorporating the invention, the burner drums or chimneys being removed in Fig. 2, although their positions are indicated in said view by dot-and-dash lines; Fig. 3 is a fragmentary sectional side elevation of the combustion device or burner set on a scale considerably enlarged over that of Figs. 1 and 2; Fig. 4 is a transverse section through the structure, the plane of section through the lower portion of the structure being indicated by the line 4-4 of Fig. 3; Fig. 5 is a plan view of the bottom member of the burner body; Figs. 6, 7, 8 and 9 are sections on the section lines 6-6, 'l1, 3-8, and 99 of Fig. 5; Fig. 10 is a plan view of the top member of the burner body; Fig. 11 is a central longitudinal section through the same on the line H H of Fig. 10; Figs. 12 and 13 are a plan view and transverse section, respectively, of one of the bafiies; Figs. 14 and 15 are similar views of another baflie used in conjunction with the one illustrated in Figs. 12 and 13, and Figs. 16 and 17 are a plan and side elevation of one of the braces used inside the burner body.

The combustion device herein disclosed is a three burner unit which, as a self-contained outfit, includes a fuel reservoir. Inasmuch as the present device is for use in an intermittent absorption refrigerating machine having a heating period whose duration amounts to only a small fraction of a complete cycle of operation, and to the end that the operation of the machine be made as nearly automatic as possible, the fuel capacity of the device is limited to such a quantity of fuel as will sustain a single heating period. Upon exhaustion of the fuel the combustion device will go out and, by reason of the cessation of heat, the cooling condensing phase of the cycle of operation will begin, and continue until time for the next heat. Therefore, in a more limited aspect, the invention has to do with an improved burner set for refrigerating machines of the class above referred to, and as such is directed to features improving the construction and operation of such a device and facilitating the handling and care thereof.

The burner body, designated generally by the reference numeral I, is made up of a bottom member 2, and a top member 3. The former, shown in detail in Figs. 5 to 9, is preferably dieformed from relatively heavy sheet metal. It includes a peripheral wall t that surrounds an oblong body portion 5 and has its lower edge turned outwardly to provide a horizontal base flange 6. The body portion Ehas openings 7 surrounded by depending flanges 8, and the parts adjacent said openings, together with the marginal portion designated 5), are in a common plane, while the remainder of said body portion is depressed to form a sump ill, the same including channels w and W adjacent the ends and sides, respectively, of the member 2. At one end of the member 2, the peripheral wall ii and flanges 6 are interrupted by a notch 12, and adjacent the same a hollow boss l3 depends from the body portion 5 in communication with the contiguous channel til The top member 3 of the burner body, shown in detail in Figs. 10 and 11, is also preferably dieformedfrom a single piece of sheet metal, desirably lighter than that of member 2, and the same comprises a horizontal wall l5 and a substantially vertical peripheral wall it; from the lower edge of which a flange l l extends outwardly. The top member 3 telescopes snugly over the bottom member 2 with the wall it of the former embracing the wall l of the latter and with the flanges l7 and 6 in engagement with each other. A fluid-tight joint is suita ly effected between the interengaged parts of the two members, as by welding, soldering or brazing. A notch E8, in one end of the wall i6 and flange ll, registers with the notch 12 of the bottom member 2, and these notches accommodate a relatively short,

downwardly curved conduit 2e whose inner end is suitably connected to the body, portion of the member 2 about the previously mentioned boss i 3. Openings are formed in the horizontal wall i5 of the topmember 3 in axial alignment with the openings 'l of the bottom member, and the material about the openings in said wall i5 is extended upwardly, thence inwardly and again upwardly to provide outer burner tubes 22 having circumferential seats 23 for a purpose which will presently appear, said seats being depressed slightly, inwardly of their outer peripheries. Inner burner tubes 2d have their lower ends fitted within and secured to the flanges 8 that surround the openings 7 of the bottom member 3 and are thus supported with their upper ends in substantially the plane of the upper ends of the outer burner tubes 22. Annular internal seats 25 extend about the inner tubes 2d and are similar in character to, and are in the same plane as, the outer seats 23. The parts designated 22 and 24 are termed burner tubes because, while extending upwardly along the inner and the outer surface of the wick, they do not contact the wick and exercise any guiding function with respect thereto, as the wick is not raised and lowered.

Supported by members '26, that extend across the inner burner tubes 24 adjacent their lower ends, are centering pins 27! for commingling tube assemblies including perforated, dished plates 28 that are formed with central apertures 29 for the reception of said pins 2'7, which apertures are surrounded by upwardly converging walls designed to cooperate with the tops of the pins 27 to assist in properly locating the commingling tube assemblies as they are lowered into operative position. Inner and outerperforated commingling tubes 36 and stare included in each of said assemblies and their lower ends rest as lighting rings, the same being designated 35,

each consisting of a cylindrical body of asbestos or the like. These are, in effect, wicks, although they are not consumed in the manner of fabric wicks, and some combustion devices that incorporate them are commonly referred to as wickless burners. However, where the term wick is employed in the claims appended hereto it is to be understood as embracing lighting rings of the general character above described, or any equivalent thereof that serves to conduct liquid fuel by capillary attraction from a source of supply to the combustion space thereabove.

To impart rigidity to the burner body, cross braces 36, spaced apart longitudinally of said body (Fig. 2), are connected along their upper edges and at their ends to the respective walls 65 and it of the top member and bear at intervals along their lower edges upon the body portion 5 of the bottom member 2 (Figs. 3, l6 and The peripheral portions of annular baffles 38 are suitably connected to the inner side of the wall ii: of the member 3 about the openings surrounded by the outer burner tubes 22. Tongues 39 extend downwardly from the outer edges of the baffles 38 and are extended through slots Q6 in frusto-conical baflles l, the lower ends of said tongues being twisted to secure the parts to gether. The baffles 38 and ii are shown in detail in Figs. 12 to 15.

Communicating with and fastened to the outer end of the previously mentioned conduit 28 is a dispensing receptacle 45, in the nature of a cup, that supports a bottle-like reservoir 36 in inverted position with the lower end of said reservoir within the receptacle. Applied to the neck 41 of the reservoir is a screw cap 49 containing a valve (not shown) that is unseated against the tension of a closing spring 5d when the headed end of the stem 5i of the valve engages the bottom of the receptacle. The reservoir is held at a proper elevation by the engagement of a. circumferential shoulder 52 thereof with the top of the receptacle and when so supported, it establishes a liquid level (indicated by the broken line a in Fig. 3) within the receptacle and within the fuel container of the burner, provided by the hollow body 5. In order to protect the reservoir and dispensing receptacle from the intense heat of the combustion device a shield Ed is supported between the two as by brackets 55 that extend from the receptacle. The shield is preferably formed from a sheet of metal that is bent at its longitudinal center, as shown at 56, to provide spaced parallel members having their extremities properly spaced apart and connected together through tongues 51 that are struck from the lower corners of one of the members. The folded portion 56 is slotted at 58 (Figs. 2 and 4) to promote circulation of air through the space between the said members.

Runners 66, shown as angular in cross section, are connected to the opposite sides of the burner body and these are adapted to be slidably engaged within inwardly facing channel members or rails 65 (Fig. 4) that are connected together by ties, one of which is shown at 62, said ties serving also to support said rails from a part 63 of a refrigerating machine. To facilitate handling of the combustion device or burner set, and the sliding of it into and out of the refrigerating machine, a handle 64 is secured to the front side of the dispensing receptacle 45.

When a reservoir 46, containing a supply of fuel, is placed in inverted position within the receptacle l5, the fuel will flow therefrom into said receptacle and through the conduit 20 into the fuel container or body of the combustion device until throughout the system a liquid level is attained to the height indicated by the broken line a in Fig. 3. The lighting rings or wicks 35, becoming saturated, conduct the fuel by capillary attraction to the combustion spaces contiguous to their upper ends and between the commingling tubes 3i; and 3!. The device is now ready for lighting, and this may be accomplished by lifting the drums or chimneys 32, with the enclosed commingling tubes, and applying a light to the wicks or rings 35. This is done, of course, when the burner set is withdrawn from the refrigerating machine, and upon replacing the drums or chimneys, the burner set may be slid back into operative position. The device functions as a wick burner in that the fuel is drawn up the lighting rings or wicks by capillary attraction from the supply in the burner body to the vaporizing and combustion zone adjacent the upper ends of said rings or wicks. As the operation of the device gets under way, the commingling tubes and adjacent parts of the burner body, including the bottom member 2, become heated to a temperature above the boiling point of water. Consequently any water that is present in the fuel, upon reaching the sump l0, flashes into steam which rises through the body of oil and accumulates within the relatively large steam space in the upper portion of the fuel container or burner body above the level of the fuel therein, and said steam will escape through the wick slots between the burner tubes into the combustion spaces thereabove where any oil that is present in the steam will be consumed. Much, if not all of the oil with which the steam is laden, however, will be extracted by the bafiles 38 and M as the vapors follow the tortuous path of escape defined thereby. While the water, which reaches the burner body in relatively small quantity, is vaporized and disposed of in the manner above described, the oil does not vaporize in the body of the burner.

From the foregoing it will be that our invention insures safe operation of the device without special attention being given it because any water that finds its way to the fuel container of the burner set is disposed of automatically and in such manner as not to adversely affect the operation of the device.

Also it will be clear that, while we have specifically described and illustrated a burner incorporating a lighting ring-the equivalent of a wick as hereinbefore pointed out, the invention, in its broadest aspect, may be applied to combustion devices of various kinds.

Having thus described our invention, what we claim is:

1. A liquid fuel burner comprising a broad and relatively shallow fuel container, the top wall of said container having an opening surrounded by a biuner tube, a second burner tube rising from the bottom wall of the container within the former tube and spaced therefrom to provide an annular wick slot, a cylindrical wick within said slot in spaced relation to the first mentioned burner tube, a bafi'ie in the form of an annulus relation thereto, and means maintaining a given fuel level within the burner body.

2. A liquid fuel burner comprising top and bottom members joined at their peripheries and so shaped as to provide a broad and relatively shallow fuel container, the top member having an opening surrounded by a burner tube, a second burner tube rising from the bottom member within the former tube and spaced therefrom a to provide an annular wick slot, a cylindrical Wick within said slot in spaced relation to the first mentioned burner tube, a bailie in the form of an annulus surrounding the wick and having its peripheral portion attached to the inner side of the top member, a second bafile in the form of an inverted frusto-conical plate suspended from the first bafiie in spaced relation thereto, commingling tubes and a chimney supported in operative relation to the burner tubes, and means maintaining a given fuel level within the burner body.

3. A liquid fuel burner comprising top and bottom body members having horizontal body portions, the horizontal body portions of the two members having a plurality of openings, those of the top member being substantially in axial alignment with the corresponding ones of the bottom member, the material surrounding said openings in the top member being formed to provide outer burner tubes having external circumferential seats adjacent their upper ends, while the material surrounding said openings in the bottom member is flanged downwardly about said openings, inner burner tubes having their lower ends fitted within and joined to said flanges and rising within the outer tubes in spaced relation thereto and having internal circumferential seats, commingling tubes supported with their lower ends within the seats of the burner tubes, a chimney enclosing the commingling tubes, a wick within the space between the burner tubes, and means supplying fuel to the burner body and maintaining a given liquid level therein.

4. A liquid fuel burner comprising, in combination, a relatively shallow metallic oil container incorporating inner and outer burner tubes rising a short distance above its top wall, said tubes being substantially concentric and spaced apart to provide a wick slot and having external annular seats near their upper ends, commingling tubes resting upon said seats, the bottom wall of the container being formed with a water collecting sump that is out of vertical alignment with the wick slot, a wick extending upwardly from inside the container through the slot and occupying substantially less than the entire area thereof, and means maintaining a maximum oil level in the container at a definite distance below the top thereof.

5. A liquid fuel burner comprising, in combination, a relatively shallow metallic oil container incorporating inner and outer burner tubes rising a short distance above its top wall, said tubes being substantially concentric and spaced apart to provide a wick slot and having'external annular seats near their upper ends, commingling tubes resting upon said seats, the bottom wall of the container being formed with a water collecting sump, baflle means between the sump and wick slot, a wick extending upwardly from inside the container through the slot and occupying substantially less than the entire area thereof, and means maintaining a maximum oil level in the container at a definite distance below the top thereof.

6. A liquid fuel burner comprising, in combination, a shallow oil container including a relatively flat top wall having a wick slot and a similar bottom wall provided with a well defined water collecting sump that is out of vertical alignment with said slot, a wick within the slot occupying less than the entire area thereof, the top portion of the interior of the container constituting a steam space that is vented through the wick slot, the aforesaid sump being so related to the combustion space thereabove as to result in its receiving sufficient heat therefrom to elevate its temperature above the boiling point of Water when the burner is in normal operation.

'7. A liquid fuel burner comprising, in combination, a shallow oil container including a relatively fiat top wall having a wick slot and a similar bottom wall provided with a well defined Water collecting sump, a wick within said slot occupying less than the entire area thereof, the top portion of the interior of the container constituting a steam space that is vented through the wick slot, the aforesaid sump being so related to the combustion space thereabove as to result in its receiving sufilcient heat therefrom to elevate its temperature above the boiling point of water when the burner is in normal operation, and oil arresting means within the container adjacent the wick slot.

LEE S. CHADWICK. WILBUR G. MIDNIGHT. 

